ASTM D543 Practice A - IMMERSION TEST
Procedure II: Mechanical Property Changes
Procedure II: Mechanical Property Changes
4.1 Test Specifications and Procedure Laminate coupons were immersed in the chemical reagents for a seven-day period in the same manner as Practice A - Procedure I. Immediately following the seven day immersion period each coupon was visually evaluated and mechanically tested in accordance with ASTM D790 "Three Point bending".
4.2 Test Laminate coupons
Test laminate coupons for the astm d543 Practice A, Procedure II test were cut from Saint-Gobain Technical Fabrics Plates 12, 15, 19, and 22. All test laminate coupons measured approximately 100 mm in length by 25 mm in width and 5 mm in depth. Dimension measurements were measured using a digital calliper accurate to ±0.005 mm. While measuring the laminate coupons, it was noted that the specimen edges were at a slight angle with respect to the depth of the material. This slight angle resulted in laminate coupons being moderately wider on one face (top compared to bottom). This slight angle is a characteristic of the JetCut process.
A total of 30 laminate coupons were tested: three laminate coupons for each of the 10 chemical reagents.
A total of 30 laminate coupons were tested: three laminate coupons for each of the 10 chemical reagents.
4.3 Test Equipment
For each chemical reagent, three laminate coupons were placed in a plastic container with a lid and held at room temperature. The laminate coupons were mounted on small stainless steel discs (3 mm in diameter and depth of 1 mm) to ensure that most of the specimen surface area was in contact with the reagent.
The ASTM D790 flexural testing portion of the ASTM D543 Method A test was performed using a test fixture. The load was applied at a constant rate of deformation using a universal test machine manufactured by Wykenham Farrance Engineering Ltd. of Slough England. The test machine uses a gear that drives the test platform upwards or downwards at a constant rate. Load readings were monitored using a 4448 N (lOOOlbf) load cell. Extension readings were monitored using a 25 mm displacement transducer, APEC model HS25. A Sciemetric 200 system was utilized for all data acquisition. Loading noses had a radius of 4.9 mm.
4.4 Test Results
Testing was conducted from May 28, 2001 to August 20, 2001. In total 30 laminate coupons were tested. The laminate coupons were named using the same labelling scheme described in Section 3.4. The data sheets and data plots for each test are located in the CD attached to this report.
Testing was conducted from May 28, 2001 to August 20, 2001. In total 30 laminate coupons were tested. The laminate coupons were named using the same labelling scheme described in Section 3.4. The data sheets and data plots for each test are located in the CD attached to this report.
4.5 Analysis of Test Data
Tables 4.1 and 4.2 summarize the results of the flexure testing on the chemically exposed laminate coupons. Figure 4.1 shows the definition of yield and ultimate flexural stress (load) and strain. The flexural yield stress is the first sudden deviation from the initial linear portion of the stress-strain curve and the ultimate flexural stress is the peak stress. Yield and ultimate flexural strains correspond to the yield and ultimate stress. It should be noted the location of the yield stress is not always a distinct point on the stress-strain
curve. Thus, the location of yield point definition can be subjective on some stress-strain plots. In this report all attempts were made to ensure consistent yield stress determination.
Figure 4.2 shows the normalized flexural yield stress and yield strain for laminate coupons exposed to chemical reagents then tested in accordance with ASTM D790 (three point bending). The data was normalized with respect to February 9, 2001 non-exposed minimum flexural stress and strain data. Non-exposed minimum values were used due to the variation inn test results illustrated in Figure
Figure 4.2 Average Chemical exposed laminate coupon yield stress and yield strain data normalized using February 9, 2001 minimum non-exposed ASTM D790 three-point flexure test data.
Based on Figure 4.2 the following conclusions may be drawn.
1. All chemical reagents except 20% Sulphuric acid appear to reduce the laminate flexural yield stress and strain.
2. 20% Sulphuric Acid appears to increase the flexural yield stress by 8% and decrease the flexural yield strain by 5%. Thus, 20% Sulphuric Acid appears to increase in the laminate flexural modulus.
Based on Figure 4.2 the following conclusions may be drawn.
1. All chemical reagents except 20% Sulphuric acid appear to reduce the laminate flexural yield stress and strain.
2. 20% Sulphuric Acid appears to increase the flexural yield stress by 8% and decrease the flexural yield strain by 5%. Thus, 20% Sulphuric Acid appears to increase in the laminate flexural modulus.
3. Water and 1% Sodium Hypochloride appears to decrease the laminate flexural yield stress and strain by less than 10 percent.
4. 1% Ferric Chloride, 5% Ammonium Hydroxide, and 5% Sodium Hydroxide show a 11 to 15% decrease in the laminate flexural yield stress and less than 10% decrease in flexural strain.
5. 1 % Nitric Acid and 0.1 % Detergent show a 18 and 14% decrease in laminate flexural strength and a 13 and 21 % decrease and the flexural strain, respectively.
6. 0.1% Soap and BOD greater than 700 PPM appears to significantly lower the flexural yield stress by 31 and 63% respectively and decrease the flexural yield strain by 14 and 10% respectively. Thus, 0.1% Soap and BOD greater than 700 PPM appear to significantly reduce the laminate flexural modulus.
Table 4.3 shows the laminate test coupon dimensions after seven-day of immersion in the chemical reagents and prior to flexural testing in accordance to ASTM D790. Two of the BOD test coupons (12_10a and 12_10c) were cut from test Plate 10 while the third test coupon (1 l_10b) was cut from Plate 11. It should be noted that the depth of these three test coupons depths (5.70, 5.61, and 5.68 mm) are significantly deeper than the average test coupon depth of 4.94 mm. Further testing and analysis is required to determine if plate depth has an influence on the test results.
Figures 4.3 and 4.4 show the flexural stress - strain responses for laminate coupons after seven-days of immersion in 0.1% soap and BOD greater than 700 PPM. Compared with non-immersed flexural tests performed on February 9, 2001 (Figure 1.1) 0.1% soap and BOD appear to significantly decrease the laminate yield stress, ultimate strain and laminate flexural modulus.
Figure 4.4 Flexural laminate coupon stress strain response after seven-day immersion in BOD greater than 700 PPM.
To check the integrity of Plate 11, three additional coupon from Plate 11 (11-6, 11-7 and 8) that were not subject to chemical reagents were tested in accordance to ASTM D790 in three-point bending loading. The flexure stress - strain response for the three non-exposed coupons from Plate 11 along with Phase I maximum and minimum flexural responses are shown in Figure 4.5. When compared to initial Phase II laminate tests (Figure 1.1) Plate 11 shows considerably more variation in the test results. It should also be noted that Plate 11 test coupons depth varied between 4.81 to 5.05 mm while the depth of the coupons tested on February 9 varied between 5.01 to 5.06 mm and coupon 1 l_10b reported in Figure 4.4 had a depth of 5.61 mm. Thus, Plate 11 appears to have significantly more variation in plate depth than the other plates.
Figure 4.5 Non-immersed Plate 11 and Phase I laminate coupons maximum and minimum flexural response in accordance to astm d543 three-point bending.
Coupon ll_10b stress-strain response, shown in Figure 4.4, appears to be significantly lower than the tests results reported in Figure 4.5. This would indicate that immersion of the coupon in BOD greater than 700PPM could reduce the laminate flexural properties.For details to know please visit here http://ussewer.com
Coupon ll_10b stress-strain response, shown in Figure 4.4, appears to be significantly lower than the tests results reported in Figure 4.5. This would indicate that immersion of the coupon in BOD greater than 700PPM could reduce the laminate flexural properties.For details to know please visit here http://ussewer.com
